The direct conversion of `A` to `B` is difficult, hence it is carried out as
`A rarr C rarrD rarr B`
Given, `DeltaS_((A^rarrC)) = 50 eU,DeltaS_((C^rarrD))=30eU,DeltaS_((BrarrD))=20 eU`, where `eU` is entropy unit. Thus the change in entropy in `(A rarrB)` is:

Options

A. `100 eU`
B. `60 eU`
C. `-100 eU`
D. `-60 eU`

Explanation

To solve the problem of finding the change in entropy from A to B through the intermediate steps, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the given entropy changes**:
- \( \Delta S_{(A \rightarrow C)} = 50 \, \text{eU} \)
- \( \Delta S_{(C \rightarrow D)} = 30 \, \text{eU} \)
- \( \Delta S_{(B \rightarrow D)} = 20 \, \text{eU} \)
...