Context: Two identical aquariums were next to an open window. One aquarium had a plastic cover on it, and the other was uncovered. This table shows how the temperature of each aquarium changed over 1.5hours.
During this time, thermal energy was transferred from () to ().
A. each aquarium . . . the surroundings
B. the surroundings . . . each aquarium
Pick the correct answer from the listed options and provide the letter of the selected option.

A