Answer: Option C

 -     Given expression = 8.7 - [7.6 - (6.5 - (5.4 - 2.3))]      = 8.7 - [7.6 - (6.5 - 3.1)]        = 8.7 - (7.6 - 3.4) = 8.7 - 4.2 = 4.5

Step 1: Simplify the innermost parentheses, starting with 4.3-2:
4.3-2 = 2.3
Step 2: Replace the parentheses with the result of Step 1:
5.4-2.3 = 3.1
Step 3: Simplify the next set of parentheses:
6.5-3.1 = 3.4
Step 4: Replace the parentheses with the result of Step 3:
7.6-3.4 = 4.2
Step 5: Simplify the last set of parentheses:
7.6-4.2 = 3.4
Step 6: Replace the parentheses with the result of Step 5:
8.7-3.4 = 5.3
Step 7: Simplify the outermost parentheses:
8.7-4.2 = 4.5
Therefore, the expression simplifies to 4.5.