C++ Which of the following is a correct way to ensure that once we read a nonnegative value into x, the loop will stop? (1) int x; while(x > x; if(x =0”; } (2) int x; for(cin >> x ; x > x; cout =0”;...

C++

Which of the following is a correct way to ensure that once we read a nonnegative value into x, the loop will stop?

(1)

int x;
while(x <>
cin >> x;
if(x <>
cout < “x="" must="" be="">=0”;
}

(2)

int x;
for(cin >> x ; x < 0="">
cin >> x;
cout < “x="" must="" be="">=0”;

(3)

int x;
do{
cin >> x;
if(x <>
cout < “x="" must="" be="">=0”;
}

(4)

int x;
cin >> x;
while(x <>
cin >> x;
cout < “x="" must="" be="">=0”;
}

Choices:

a. 2 and 4

b. 3 and 4

c. 2 and 3

d. 1 and 3