**Core Concept**
The Employees' State Insurance (ESI) Act provides various benefits to insured persons, including medical care, disability benefits, and cash compensation for sickness. This question tests the understanding of the ESI Act's provisions related to sickness benefits.

**Why the Correct Answer is Right**
The ESI Act pays sickness benefits to insured persons for a specific period, calculated as a percentage of their average daily wages. The daily rate is a fraction of the average daily wages, and the total number of days for which the benefit is payable is a critical aspect of the ESI Act. The correct answer will provide the specific number of days and the fraction of the average daily wages.

**Why Each Wrong Option is Incorrect**
**Option A:** This option may be incorrect because the actual number of days and fraction of average daily wages may differ from the values stated in this option.

**Option B:** Similarly, this option may be incorrect for the same reason as Option A.

**Option C:** This option may be incorrect because the actual values for the number of days and fraction of average daily wages are different from those stated in this option.

**Clinical Pearl / High-Yield Fact**
It's essential to remember that the ESI Act provides cash compensation for sickness, which is a crucial benefit for insured persons. The actuarial rates and maximum duration of sickness benefits are subject to change, so it's vital to stay updated on the latest provisions.

**Correct Answer: C. 90 days, 70%**