Biggest oil spill occurred in

Options

A. March 1989 off Alaska by Exxon Valdez
B. 1968 off south America by World Glory
C. October 1997 off Singapore
D. February 1991 in Persian Gulf.

Answer

**Step-by-Step Solution:**

1. **Understanding Oil Spills**: An oil spill is defined as the accidental release of petroleum or liquefied hydrocarbons into the environment, particularly in water bodies or on land. It is a significant form of environmental pollution that can have devastating effects on marine life.

2. **Identifying Major Oil Spills**: The question asks for the biggest oil spill in history. To answer this, we need to consider notable oil spills and their impacts.

3. **Reviewing the Options**:
- March 1989 in Alaska by Exxon Valdez
- 1968 in South America by Walter Bloom
- October 1997 in Singapore
- February 1991 in Persian Gulf

4. **Analyzing Each Option**:
- The Exxon Valdez spill in 1989 was significant but not the largest.
- The 1968 spill by Walter Bloom is not widely recognized as one of the largest.
- The October 1997 spill in Singapore is also not among the largest recorded spills.
- The Persian Gulf spill during the Gulf War in February 1991 is known to be one of the largest oil spills in history, releasing approximately 1,818 to 1,091 tons of crude oil.

5. **Conclusion**: Based on the analysis, the biggest oil spill occurred in February 1991 in the Persian Gulf during the Gulf War.

**Final Answer**: The biggest oil spill occurred in February 1991 in the Persian Gulf.

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