Answer:
B) A rectangle with a length of 15 cm and a width of 9 cm
Explanation:
we know that
If two figures are similar, then the ratio of its corresponding sides is proportional
Verify each cases
case A) A rectangle with a length of 9 cm and a width of 6 cm

therefore
The rectangle case A) is not similar to rectangle A
case B) A rectangle with a length of 15 cm and a width of 9 cm


therefore
The rectangle case B) is similar to rectangle A
case C) A rectangle with a length of 14 cm and a width of 7 cm

therefore
The rectangle case C) is not similar to rectangle A
case D) A rectangle with a length of 12 cm and a width of 8 cm

therefore
The rectangle case D) is not similar to rectangle A