The answer is A Evaluation
The description talks about Richard's work, it resembles a manager's evaluation -mostly during training processes in some jobs-
Incorrect answers:
B Experience
Experience cannot be used as the correct word because all the information is related to Richard's work if in any case, a person would use experience, the expression should be in my experience working with Richard...
C) Guess
A lot of precise and concise elements are enlisted in this description which does not leave any space for expectations
D) Trial
Trial can only be used in a legal context and we do not have any evidence that this is a legal situation.
A green wavy actually would underline the text that may be incorrect grammatically. So it would be FALSE.
The echoing sound of his voice shows his excitement that his brother is communicating