Final answer:
The use of overly positive or harsh language suggests the presence of bias, which indicates a lack of objectivity in writing and can reveal an underlying agenda.
Therefore, option A is correct.
Step-by-step explanation:
Overly positive or overly harsh language is a sign of bias. Bias in language can manifest as the use of language that is offensive, demeaning, or prejudicial towards individuals or groups. This can skew the writer's message and interfere with the intent to communicate a fair and balanced point of view. Recognizing bias is essential when evaluating sources for credibility, as biased language can indicate an underlying agenda or a lack of objectivity. It is important for writers to maintain an objective voice and provide a balanced view to avoid the pitfalls of biased language, especially when attempting to address complex topics and present thorough research.