Who proposed the double helix model of $DNA$?

In $DNA$,the complementary bases are,

In $DNA$,the two polynucleotide chains are . . . . . . .

What is deoxyribonucleic acid $(DNA)$?

Which of the following options is incorrect regarding $DNA$ base pairing rules (Chargaff's rules)?

Who proposed the following statement?
"It has not escaped our notice that the specific pairing we have postulated immediately suggests a possible copying mechanism for the genetic material."