Final answer:
Benedick and Beatrice pretend to have a toothache and stuffy nose to deny their love in Shakespeare's 'Much Ado About Nothing'. Therefore, the correct option is d. toothache and stuffy nose.
Step-by-step explanation:
In the play 'Much Ado About Nothing' by William Shakespeare, the characters Benedick and Beatrice both pretend to have ailments as excuses for their changes in behavior due to their newfound love for each other. They specifically pretend to have toothache and stuffy nose. This comedic element reflects the characters' reluctance to admit their true feelings openly, adding humor and depth to their complex relationship.