The correct option is
B total
In order to fill in the blank with the most suitable adjective or an adverb, let's understand what adjectives and adverbs are.Adjectives are the words that define/explain nouns or pronouns. For example: Roshni is pretty. Here, 'Roshni' is the noun and 'pretty' explains how she is, hence 'pretty' is the adjective.
Adverbs are the words that describe action words (verbs). For example: Ram fought bravely. Here, 'Ram' is the noun and 'fought' is the verb. 'Bravely' describes how he fought, hence it is the adverb.
NOTE: We need a word to describe failure. Since, 'failure' is an abstract noun, the word that describes it is called an adjective. Hence, we need an adjective to fill in the blank.
Option B - 'Totally' is an adjective, which means completely and in the sentence, the person is a complete failure and not 'completely failure'. Hence, option B is incorrect.
Option C - 'Totaling' is the participle form of the verb 'total' and it is not an adjective. Thus option C is incorrect.
Option D - 'Totalness' is a wrong word. Hence, option D is incorrect.
Option A - 'Total' is an adjective which can be used to describe the failure. Hence, option A is the correct answer.
'Her eldest daughter is a total failure.'