data structer (java)

Suppose that Si and S2 are empty stacks and al, a2 and a3 are objects. What do the stacks contain after executing the following sequence of operations? s1.push(a2), Si.push(al), S2.push(a3); S2.push(S1.pop(), S2.push(S1.peek(). Select one: O A. SI= [a2, al ] and S2-la,3,a3, al] O B. S1-la2) and S2-[a3 al, a2] O C. S1-11 and 52-la,3, al] O D. S1=1) and S2-11 Data abstraction: the separation of data type's properties from its + Select one: O a. logical implementation O b. operation, task O c. Not logical implementation O d. data type data structure