Answer:
b. The flower bloomed earlier than expected.
Step-by-step explanation:
The other three have 'was' before the verbs; 'the athlete was penalized', 'the child was fed', 'he was convinced', etc. This puts these three sentences in the passive voice. While, 'the flower bloomed earlier than expected' shows the flower acting the verb, rather than the verb acting on it, thus making putting it in the active voice.
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