Assertion: Environmental deprivation has been found to lower intelligence.

Reasoning: Rich nutrition, good family background, and quality schooling have been associated with increased intelligence.

Both the assertion and reasoning are true, and the reasoning is the correct explanation of the assertion.

The correct answer is Option 1: Both the assertion and reasoning are true, and the reasoning is the correct explanation of the assertion.

Assertion: Environmental deprivation has been found to lower intelligence. This is correct. Environmental deprivation — such as lack of stimulation, poor nutrition, and low-quality education — has been shown to negatively impact cognitive development and lower intelligence.

Reasoning: Rich nutrition, good family background, and quality schooling have been associated with increased intelligence. This is also correct. Positive environmental factors like rich nutrition, supportive family background, and quality education contribute to better intellectual growth.

Since the reasoning directly explains why environmental deprivation can lower intelligence — by highlighting what supportive environments provide — it is the correct explanation of the assertion.