In the following question, out of the given four alternatives, select the alternative which best expresses the meaning of the Idiom or Phrase.
To keep an eye on

Correct option is D

Option (d) is the correct meaning of the given idiom.
To keep an eye on: To observe closely and carefully. (नज़र रखना)
Example: Please keep an eye on the kids while I cook.
Other related idioms:
Keep tabs on – To watch or track someone/something carefully. (Hindi: ध्यान देना)
Monitor – To observe or supervise regularly. (Hindi: देखरेख करना)