As per the given description in the sentence,the word that best complete the sentence would be 'excursion'as it denotes 'a brief recreational or refreshing trip or journey that is deviation from the usual way' which best compliments the meaning of the sentence.
The family's trip to the shore during summer primarily intends to spend some leisure time together leaving all the worries or usual activities behind exemplify 'excursion'. Thus, <u>option A i.e. 'excursion'</u> is the correct answer.
