The correct option is D whining
'Whimpering' means making small, weak sound expressing pain, especially which animals do. The meaning of 'Whimpering' is 'whining', Option C. It means making a high pitched cry or sad sound. Option A 'barking' is what dogs do. Option B 'crying' is the act of crying. Option D 'Sobbing' means crying. So, the most apt word as the meaning of the word 'whimpering' is Option C, Whining.