Options B and C are the correct answers because the prepositions 'from' and 'to' are generally used in sentences to indicate that something or someone is moving from one place to the another or vice versa. 'To' is used to indicate the place, person, or thing that someone or something moves toward, or the direction of something, 'at' refers to a specific time or place while 'from' is used to show where somebody/something starts.
Option A is incorrect because 'at' refers to a specific time or place while 'in' is used for unspecific times during a day, month, season, year or for a location. Neither indicates any sort of movement from one place to another.Option D is incorrect because while 'to' can be used to indicate the place, person, or thing that someone or something moves toward, or the direction of something, 'at' refers to a specific time or place. Using 'at' in the second blank would hence be grammatically incorrect.