A Executed a Will with B, C & D as Witnesses

A executed a will with B, C & D as witnesses. At the time of the subscription by A, C & D on each and every page of the will, B was outside the room with an open door. Is the will valid?

A) The will is void because it was not subscribed in his presence.
B) The will is valid because the phrase "in the presence" does not mean actual seeing but mere opportunity to have witnessed and seen the signing.
C) The will is valid because there is substantial compliance with the law.
D) The will is void because it requires the presence of the witnesses to prevent fraud, in the execution of the will and to protect the integrity of the will.