Find the synonym of the underlined word: 

The elegant decorations transformed the garage into a ballroom. 

'Transform' means to significantly alter the form, nature, or appearance of anything.

"Lasers have revolutionized cardiac surgery."

'Transform' refers to change in this context "The exquisite decorations transformed the garage into a ballroom." As a result, option B is valid and the other options are incorrect because they do not give the necessary information.

Reverted is the verb form of the verb (an earlier state, condition, situation, etc.) She has returned to her previous behaviours. The pressure in my blood has returned to normal. He seemed to have returned to (his previous) form after doing poorly in the previous two games.

Sustained means to provide support, relief or sustenance on a sustained basis i.e. nurture, maintain, extend.