Answer:
The equivalent program in C++:
#include<iostream>
#include <sstream>
using namespace std;
int main(){
    string Score, Rank;
    cout<<"Enter student score and class rank: ";
    cin>>Score>>Rank;
    int testScore = 0, classRank = 0;
    stringstream sstream(Score);
    sstream>>testScore;
    
    stringstream tream(Rank);
    tream>>classRank;
    
    if (testScore >= 90){
        if(classRank >=25){cout<<"Accept";}
        else{cout<<"Reject";}
    }
    else if(testScore >= 80){
        if(classRank >=50){cout<<"Accept";}
        else{cout<<"Reject";}
    }
    else if(testScore >= 70){
        if(classRank >=75){cout<<"Accept";}
        else{cout<<"Reject";}
    }
    else{cout<<"Reject";}
    return 0;
}
Explanation:
This declares Score and Rank as string variables
    string Score, Rank;
This prompts the user for score and class rank
    cout<<"Enter student score and class rank: ";
This gets the user input
    cin>>Score>>Rank;
This declarees testScore and classRank as integer; and also initializes them to 0
    int testScore = 0, classRank = 0;
The following converts string Score to integer testScore
<em>    stringstream sstream(Score);</em>
<em>    sstream>>testScore;</em>
The following converts string Rank to integer classRank
    stringstream tream(Rank);
    tream>>classRank;
The following conditions implement the conditions as given in the question.    
If testScore >= 90
<em>    if (testScore >= 90){</em>
If classRank >=25
<em>        if(classRank >=25){cout<<"Accept";}</em>
If otherwise
<em>        else{cout<<"Reject";}</em>
<em>    } ---</em>
If testScore >= 80
<em>    else if(testScore >= 80){</em>
If classRank >=50
<em>        if(classRank >=50){cout<<"Accept";}</em>
If otherwise
<em>        else{cout<<"Reject";}</em>
<em>    }</em>
If testScore >= 70
<em>    else if(testScore >= 70){</em>
If classRank >=75
<em>        if(classRank >=75){cout<<"Accept";}</em>
If otherwise
<em>        else{cout<<"Reject";}</em>
<em>    }</em>
For testScore less than 70
<em>    else{cout<<"Reject";}</em>
<em />