For this case, we propose a rule of three for each amount. Then we will add 20% and see if it is less than or equal to $60, if that is true then Clay can pay the tip of 20%:
$ 48.53 ------------> 100%
x ----------------------> 20%
Where "x" represents the amount corresponding to 20%.

So, we have:

With this bill Clay could not leave a 20% tip.
$ 49.75 ------------> 100%
x ----------------------> 20%
Where "x" represents the amount corresponding to 20%.

So, we have:

With this bill Clay could leave a 20% tip.
$ 54.99 ------------> 100%
x ----------------------> 20%
Where "x" represents the amount corresponding to 20%.

So, we have:

With this bill Clay could not leave a 20% tip.
$ 61.60 ------------> 100%
x ----------------------> 20%
Where "x" represents the amount corresponding to 20%.

So, we have:

With this bill Clay could not leave a 20% tip.
$ 58.80 ------------> 100%
x ----------------------> 20%
Where "x" represents the amount corresponding to 20%.

So, we have:

With this bill Clay could not leave a 20% tip.
$ 50 ------------> 100%
x ----------------------> 20%
Where "x" represents the amount corresponding to 20%.

So, we have:

With this bill Clay could leave a 20% tip.
So, I could only tip with the options B y F
ANswer:
Option B y F