A rule states that in order to drink beer, one must be over 18 years old. In a bar, there are 4 people. $\mathrm{P}$ is 16 years old. $\mathrm{Q}$ is 25 years old, $\mathrm{R}$ is drinking milkshake and $\mathrm{S}$ is drinking a beer. What must be checked to ensure that the rule is being followed?
(A) Only P's drink
(B) Only P's drink and S's age
(C) Only S's age
(D) Only P's drink. Q's drink and S's age
A rule states that in order to drink beer, one must be over 18 years old. In a bar, there are 4 people. $\mathrm{P}$ is 16 years old. $\mathrm{Q}$ is 25 years old, $\mathrm{R}$ is drinking milkshake and $\mathrm{S}$ is drinking a beer. What must be checked to ensure that the rule is being followed?
(A) Only P's drink
(B) Only P's drink and S's age
(C) Only S's age
(D) Only P's drink. Q's drink and S's age