Step 1: Understanding the statement.
The statement suggests that environmental pollution is the cause of the increasing incidents of acid rain, which assumes a relationship between pollution and acid rain.
Step 2: Analyzing the assumptions.
(I) Environmental pollution leads to acid rains only: This assumption is not implicit because the statement does not restrict pollution to causing only acid rain; it simply connects the two.
(II) Environmental pollution is increasing: This assumption is implicit because the statement refers to increasing incidents of acid rain, which can be attributed to the growing pollution levels.
Step 3: Conclusion.
The correct answer is (B) if only assumption II is implicit, as assumption II is directly supported by the statement, while assumption I is not implied.