One of the world’s most celebrated paintings, The Man with the Golden Helmet, long attributed to Rembrandt, is not a Rembrandt after all. So say several art experts, who base their conclusion on an analysis of stylistic features, especially details both of shading and of brushwork. In order to ascertain who really painted the well-known masterpiece, the experts have begun a series of, sophisticated new tests, including one that involves the activation of neutrons. These tests yield patterns for any painter that are as distinctive as a good set of fingerprints.
Which of the following is an assumption on which the conclusion of the art experts depends

A．The Man with the Golden Helmet was not painted during Rembrandt’s lifetime.

B．If even The Man with the Golden Helmet is of questionable attribution, then any supposedly authentic Rembrandt has now become suspect.

C．The painting known as The Man with the Golden Helmet is a copy of a Rembrandt original.

D．The original ascription of The Man with the Golden Helmet to Rembrandt was a deliberate fraud.

E．(E) There are significant consistencies among authentic Rembrandts in certain matters of style.

甲股份有限公司设立5年来，尚无亏损记录，盈利水平不断上升，股本总额为人民币6 000万元，其中A公司持有占股本总额15%的股份。为了进一步提升甲公司的竞争实力，经股东大会代表75%表决权的股东同意兼并A公司，收购A公司持有甲公司的全部股票。在收购过程中有以下情况：
(1)A公司属于本公司的发起人；
(2)A公司为了购买物资开出面值800万元的商业汇票给B公司支付货款，该票据尚未到期，乙、丙两企业作为该票据的担保人。B公司提出要求A公司提前支付票款，否则到A公司被甲公司兼并后，A公司主体不存在，该票据的付款义务人不明确。
要求：根据公司法、票据法和会计法的规定，分析回答下列问题：
(1)甲公司关于兼并A公司的决议是否符合公司法的规定收购本公司发行在外的股票是否合法A公司转让持有甲公司的股票是否合法
(2)乙、丙两企业作为票据担保人，如何办理保证手续
(3)B公司要求A公司提前支付票款，理由是否成立
(4)若A公司到期不能付款，B公司可行使哪些权利