The correct option is B But
Delicious food is liked by all. 'Garnished' is an adjective used to describe food which is decorated and presented well. Food, which is garnished well, is visually appealing and hence liked by all. The given sentence states that 'Sonali prepares delicious food'. However, the food is not presented well. Hence, two contradicting or opposing things about the food prepared by Sonali are described in the given sentence. The conjunction, 'but' is used to introduce a phrase or clause which contrasts something which has already been mentioned. Hence, option B is the most appropriate conjunction to be used.
Options A and D: The conjunctions, 'and' and 'also' indicates addition. They are used to connect two statements or clauses, which are similar. They cannot be used to connect two clauses which contradict or contrast each other. Hence, options A and D are incorrect.
Option C: 'But also' is a conjunction, which is used along with the conjunction, 'not only. 'Not only' and 'but also' are always used together and are called correlative conjunctions. They connect two statements which belong to the same part of speech. As the conjunction, 'not only' is not used in the sentence, the conjunction, 'but also' cannot be used. Hence, option C is incorrect.