One form of cucumber has flowers that do not open, but they can be opened for artificial pollination. A plant with closed flowers

One form of cucumber has flowers that do not open, but they can be opened for artificial pollination. A plant with closed flowers and a plant with open flowers were crossed. In F1, all flowers are open. What is the likelihood of backcrossing F1 hybrids with both parental forms with closed flowers?

The probability of the appearance of plants with closed flowers, obtained as a result of backcrossing of F1 hybrids with a parental form with open flowers – 0, with a parental form with closed flowers – 50%.