The paragraph is followed by an incomplete phrase or sentence which summarizes the main idea of the paragraph. Choose the missing words of the phrase or sentence.

The harp seal mom nurses her pup on 48% fat seal milk continuously for 12 days without eating. Her pup will gain an average of 2.3 kg per day during this 12-day nursing period, while mom herself will lose about 3.2 kg per day.
The harp seal mom’s significant （） loss during nursing.