Respuesta :
The subjunctive in this sentence is BE. "Is" is the present form, whereas 'be' is subjunctive. The full sentence goes: 'It is essential that she (should) be at the meeting.' Just add "should" before subjunctive if you aren't sure whether it is subjunctive or not.
Answer:
a. be
Explanation:
A verb in the subjunctive mood expresses a desire, a requirement, a suggestion, a command, or a hypothetical condition, i.e. one that is contrary to fact.
In this sentence, the verb be expresses a requirement.
Choice B gives a non-subjunctive form of the verb 'be'. The form is is used in the present tense.