Which sentence is an example of a metaphor?

The bear was big and brown.

The squirrel scurried up the tree.

The cat's purr was a soft lullabye.

The lion's roar was fierce and scary.

Your answer would be: that cars purr was a soft lullaby.

Explanation: the cat doesn't actually sing a lullaby but it's soothing so it's a metaphorical lullaby.

The correct option is option (D).

Explanation:

Metaphor: A Metaphor is an implied simile. It does not, like the simile, state that one thing is like another or acts as another, but takes that for granted and proceeds as if the two things were one.

For eg: Life is a dream.