Check my most recent question im stuck T-T

What is the chemical symbol of the element located in the 5th period that naturally occurs as a diatomic solid?

Aging populations can be a problem for developed countries because a) there are fewer younger workers coming into the workforce. b) most older workers demand top-level pay and full benefits. c) many older people are skilled in manufacturing, not technology. d) younger workers cannot find jobs when older people work longer.

Which expression is equivalent to (fg)(5)