Choose the correct statement that best describes pemphigoid and/or pemphigus?
a. Pemphigoid alters the cellular connections at the basement membrane (desmosomes)
b. Positive Nikolsky sign is seen in pemphigus and pemphigoid
c. Pemphigus rarely affects the oral cavity
d. Pemphigus alters the cellular connections above the basement membrane (hemidesmosomes)
e. Pemphigoid rarely affects the oral cavity