In the given question, a sentence is given with a part of it missing and represented by a blank. Choose the phrase that can be placed in the given blank to make a meaningful and grammatically correct sentence.
The program has been around for more than a decade, _______ the shapes of galaxies.
1
empowers volunteers to prove
2
enlisting volunteers to classify
3
encroaching volunteers
4
aceepted volunteers
5
None of these