In Lederberg and Tatum's Experiments with E

In Lederberg and Tatum's experiments with E. coli auxotrophs, they found that when cells of two mutant strains were combined, ____. ​

A) cells were able to grow on minimal medium supplemented with nutrients required by the first mutant strain
B) cells were able to grow on minimal medium supplemented with nutrients required by the second mutant strain ​
C) some cells were able to grow on minimal medium ​
D) no cells were able to grow on minimal medium ​
E) cells were able to grow in liquid medium but not on gel-like medium containing agar ​