C#.NET — Identify the incorrect decision-control form among common if/else patterns.
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Aif (Condition1) { // Some statement }
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Bif (Condition1) { // Some statement } else { // Some statement }
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Cif (Condition1) { // Some statement } else { // Some statement } else if (Condition2) { // Some statement }
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Dif (Condition1) { // Some statement } else if (Condition2) { // Some statement } else { // Some statement }
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Eif (Condition1) { // Some statement } else if (Condition2) { // Some statement } else if (Condition3) { // Some statement } else { // Some statement }
Answer
Correct Answer: if (Condition1) { // Some statement } else { // Some statement } else if (Condition2) { // Some statement }
Explanation
Introduction / Context:This tests recognition of valid if/else/else-if ordering and structure in C# decision control statements.
Given Data / Assumptions:
- We compare several forms to find the one that violates syntax or structure.
Concept / Approach:In C#, else-if chains must place the else-if blocks before a final else block. After else appears, no further else-if can follow. Bracing style in examples is acceptable as shown.
Step-by-Step Solution:
Option C places "else if" after an "else" block, which is invalid structural ordering. All other options follow the correct sequence of if → zero or more else if → optional else.Verification / Alternative check:Try compiling each pattern: only option C fails because the parser does not allow else-if after else.
Why Other Options Are Wrong:
- A: simple if; valid.
- B: if/else; valid.
- D: if → else if → else; valid.
- E: multiple else if followed by else; valid.
Common Pitfalls:Misordering else-if and else, or thinking that multiple else blocks are allowed (only one else is permitted at the end).
Final Answer:Option C is the incorrect form.