Answer: the correct answer is (B) Whether others of the closely related group of plants also produce histidine in large quantities
Explanation:
This is a CAUSAL argument.
In a causal argument, A and B are observed together, and the CR concludes that A CAUSES B.
Premise = A and B are observed together:
A cultivated herb produces histidine and is able to grow in metal rich soils.
Conclusion = A causes B:
Histidine CAUSES the herb to be able to grow in metal rich soils.
One way to strengthen the conclusion that A causes B is give ANOTHER SUPPORTING EXAMPLE that links A to B.
