Which of the following sentences is NOT true?

A$.$ A complementor helps to increase the size of a firm's market, whereas a firm's competitors divide this market among a set of firms.

B$.$ Another firm is a complementor if your customers value your product more when they have this other firm's product than when they have your product alone.

C$.$ The same firm can be a complementor for one firm and a competitor for another.

D$.$ A single firm cannot be both a competitor and a complementor to the same firm.

E$.$ Entry of new complementors for a given firm can create extra value while increasing the threat of competition on the current complementors.