$60,40,55,45,50,50,$______
We can take the alternative numbers from the first term.
- $60 \overset{-5}{\rightarrow} 55$
- $55 \overset{-5}{\rightarrow} 50$
- $50 \overset{-5}{\rightarrow} {\color{Magenta}{45}}$
We can take the alternative numbers from the second term.
- $40 \overset{+5}{\rightarrow} 45$
- $45 \overset{+5}{\rightarrow} 50$
So, the correct answer is $(A).$