|This should work for Question 1 in B13 and Questions 2 & 3 in B14 and B15. Adjust as required...|
Right Click the Sheet tab for the sheet where you want this to happen and choose View Code.
Paste this code into the pane that opens. Read the comments to see what the code should do.
Private Sub Worksheet_Change(ByVal Target As Range)
'Check To See If Change Was Made To B13
If Target.Address = "$B$13" Then
'If B13 = No, Delete DropDown and Set B14:B15 to N/A
If Target = "No" Then
.Value = "N/A"
'If B13 = Yes, Clear B14:B15 and Add Yes-No Drop Downs
.Add Type:=xlValidateList, Formula1:="Yes,No"
.IgnoreBlank = True
.InCellDropdown = True