Which group of words is a gerund phrase?

"Using energy-efficient light bulbs has been helping people to cut down on waste."

A. Using energy-efficient light bulbs
B. has been helping people to cut down on waste
C. helping people
D. to cut down on waste

technical documents should be clear and precise. basically, clarity is the key element in a successful technical document.

to refer to another writer's ideas in the course of making your own original statement. when you use a summary in the course of your own writing, you must use your be used in book reviews (see chapter 8), in essays of analysis (see, nection between sentences, and you can create new paragraphs to reflect

pretty sure the answers are 1 b 2 c idk hope it is right