Choose the word or phrase that is equivalent in meaning to the given phrase:
Under a cloud
To be "under a cloud" is an idiom, so it is not about actual weather. It means to be in disgrace or out of favour because people suspect you of having done something wrong. The cloud stands figuratively for the shadow of suspicion hanging over the person.
Hence the phrase means suspected of wrong doing, option c.
If the price of a commodity increases by 25%, by what percentage should the consumption be reduced to keep the expenditure the same?