Answer: lacking strength
Explanation:
The highlighted word is ''frail''.
The definition of frail in relation to a human being is someone who is physically weak and fragile.
In this context therefore, it is logical to assume that the word means that the person being referred to (the mother) is lacking strength. This would make sense because the mother is getting old and people get weaker as they age.
Answer:B: the valve of promise
No, you always need to provide a citation.
"During the rock concert" would be the subject, as "an amplifier exploded on stage" would be the predicate.
