Answer:
The Correct answer is A: With California expected to see severe electricity shortfalls and perhaps blackouts on as many as 30 days this summer, the administration has grown increasingly concerned about
Explanation:
Option A makes perfect sense and is logical in its reasoning.
Option B and C are wrong because of their use of "as much as 30 days". "Much" cannot be counted and it was used with "days", which can be counted.
Option D and E is wrong because of their use of the word "insofar as" which means to an extent. Hence these options are implying that the administration's concern is only to an extent, while the problem being mentioned is a severe one.