Prompt analysis

a ,b, c are real numbers.

Superset

The answer to this question will be either yes or no.

Translation

In order to find the answer, we need:

1# exact value of a, b, c

2# condition or equation, so that we can infer the answer.

Statement analysis

St 1: c = a+b or b-c = -a. The condition might be true if a is negative. But nothing as such is given. INSUFFICIENT

St 2: a<0. Nothing can be said about b and c. Insufficient.

ST 1 &St 2: if a<0, that mean -a is positive and b-c is positive.ANSWER

Option C

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