“Evironmental Issues” MCQ with Answer Explanation : NEET 2025.

Here below some basic MCQ’s of Environmental Issues with answer which is explained in details. Let’s check one by one.

MCQ 1:
Which of the following gases is primarily responsible for the greenhouse effect?

A) Oxygen
B) Nitrogen
C) Carbon Dioxide
D) Argon

Answer: C) Carbon Dioxide

Explanation: Carbon dioxide (CO₂) is a major greenhouse gas, contributing significantly to the greenhouse effect. It traps heat in the atmosphere, leading to global warming. Other greenhouse gases include methane (CH₄) and nitrous oxide (N₂O), but in this list, CO₂ is the most relevant.

MCQ 2:
Which of the following is a non-renewable resource?

A) Solar energy
B) Wind energy
C) Coal
D) Geothermal energy

Answer: C) Coal

Explanation: Coal is a non-renewable resource because it forms over millions of years from decomposed plant material and cannot be replenished within a human timescale. In contrast, solar, wind, and geothermal energy are renewable resources that can be replenished naturally.

MCQ 3:
What is the primary source of marine pollution?

A) Plastic waste
B) Oil spills
C) Sewage discharge
D) All of the above

Answer: D) All of the above

Explanation: Marine pollution can originate from various sources, including plastic waste, oil spills, and sewage discharge. All these factors contribute significantly to the degradation of marine environments, affecting aquatic life and ecosystems.

MCQ 4:
Which of the following is a consequence of deforestation?

A) Increase in biodiversity
B) Soil erosion
C) Improved air quality
D) Enhanced carbon sequestration

Answer: B) Soil erosion

Explanation: Deforestation leads to soil erosion because trees that stabilize the soil are removed. Without roots to hold the soil in place, it can be washed away by rain, leading to loss of fertile land and increased sedimentation in rivers.

MCQ 5:
Which international agreement aims to combat climate change?

A) Kyoto Protocol
B) Montreal Protocol
C) Paris Agreement
D) Basel Convention

Answer: C) Paris Agreement

Explanation: The Paris Agreement is a landmark international treaty adopted in 2015 aimed at combating climate change and limiting global warming to well below 2 degrees Celsius. The Kyoto Protocol focuses on reducing greenhouse gas emissions but was more limited in scope and timeframe compared to the Paris Agreement.

MCQ 6:
What is the main cause of acid rain?

A) Carbon dioxide
B) Sulfur dioxide and nitrogen oxides
C) Ozone
D) Methane

Answer: B) Sulfur dioxide and nitrogen oxides

Explanation: Acid rain is primarily caused by sulfur dioxide (SO₂) and nitrogen oxides (NOx) that are released into the atmosphere from burning fossil fuels. These compounds react with water vapor to form sulfuric and nitric acids, which fall as acid rain.

MCQ 7:
Which layer of the atmosphere contains the ozone layer?

A) Troposphere
B) Stratosphere
C) Mesosphere
D) Thermosphere

Answer: B) Stratosphere

Explanation: The ozone layer is located in the stratosphere, approximately 10 to 30 miles above Earth’s surface. It absorbs most of the sun’s harmful ultraviolet radiation, protecting living organisms.

MCQ 8:
What is the primary component of biogas?

A) Methane
B) Hydrogen
C) Carbon monoxide
D) Ethanol

Answer: A) Methane

Explanation: Biogas is primarily composed of methane (CH₄), along with carbon dioxide (CO₂) and small amounts of other gases. It is produced through the anaerobic digestion of organic materials.

MCQ 9:
What is a significant effect of climate change on biodiversity?

A) Increase in species population
B) Habitat loss
C) Improved genetic diversity
D) Decreased competition

Answer: B) Habitat loss

Explanation: Climate change leads to habitat loss due to altered weather patterns, rising sea levels, and changing ecosystems. Many species struggle to adapt to these rapid changes, resulting in biodiversity loss.

MCQ 10:
Which of the following is a consequence of overfishing?

A) Increased fish populations
B) Ocean acidification
C) Disruption of marine ecosystems
D) Enhanced fishing techniques

Answer: C) Disruption of marine ecosystems

Explanation: Overfishing can deplete fish populations and disrupt marine ecosystems, leading to an imbalance in species interactions and affecting the overall health of the ocean environment.