Answer: A. I was not a good singer
Step-by-step explanation:
" I " is a singular noun, that represents only one person
The following auxiliary verb " is " and " are " are both forms of the root " to be ". " Is " is the singular form and " are " is the plural form.
Since " I " is a singular pronoun, then the following must be a singular verb " is "
Since both choices are in the past tense, then presumably it is in the past tense, which would be " was ".
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