The correct answer is (c) 16.
Let $x$ be the total number of inhabitants in the area. Then the number of female inhabitants is $0.4x$ and the number of male inhabitants is $0.6x$. The number of tea drinkers is $0.45x$, of which $0.2x$ are male. Therefore, the number of female tea drinkers is $0.25x$. The number of female non-tea drinkers is $0.4x – 0.25x = 0.15x$. This is equal to 16% of the total number of inhabitants.
Option (a) is incorrect because it is the percentage of male non-tea drinkers, not female non-tea drinkers. Option (b) is incorrect because it is the percentage of female tea drinkers, not female non-tea drinkers. Option (d) is incorrect because it is the percentage of male tea drinkers, not female non-tea drinkers.