简述变质岩的矿物成分特征。

张先生有100万元人民币，考虑到目前银行存款利率较低，在股市看好时，想将这笔钱来做证券投资，张先生在上海证券交易所买了10487元B公司的A股股票和8000元的B公司发行的可转换债券，并且买了正在发行的面值为100元的10年期国债，国债票面利率为5%，市场利率为5%。同时将另外的20万元投资了货币市场基金。

就其所购买的债券来说，债券上标明的利率，是债券的（）。

A.票面利率

B.市场利率

C.法定利率

D.发行利率

无错位的鼻骨闭合骨折（）

A.无需复位

B.鼻内或鼻外复位法

C.清创缝合鼻骨复位

D.开放复位

E.固定、缝合、鼻内填塞

归因理论中，任务的难易程度属于（）

A.客观、不稳定、不可控的因素

B.主观、不稳定、不可控

C.内部稳定、不可控的因素

D.外部不稳定、不可控的因素

E.外部稳定、不可控的因素

关于抗原，正确的是

A．有免疫原性

B．有免疫反应性

C．有免疫原性和免疫反应性

D．分子量大于1kDa

E．能与所有抗体结合

It sounds like a science fiction, but researchers say it’s a scientific fact: Microscopic organisms dubbed "killer algae" are paralyzing fish with unknown toxins and then eating away at their flesh. They might be making people sick, too.
The name given to this single-cell organism, or dinoflagellate, is Pfiesteria piscimorte- literally, "fish killer. " It was discovered at North Carolina State University in 1988, but at the same time, few scientists believed in its existence, much less in its highly unusual predatory nature. But ongoing research has led to international acknowledgment of the phenomenon and, recently, research funding.
Seemingly prompted by an unknown substance secreted by fish, the aggressive creature swims into action. It sends neurotoxins into the water and air, paralyzing a fish’s nervous system, and causing it to gasp for air at the surface. Eventually the fish suffocates. The killer dinoflagellate then attaches itself to the fish and begins sucking away at its flesh. This macabre scenario may help solve several sea mysteries, such as why fishermen report seeing "fish walks" (fish trying to leave the water) and pools of dead fish with holes eaten through them.
Whether humans are affected by the dinoflagellate’s toxin remains to be seen. Researchers think it’s unlikely eating fresh fish are in danger, but anyone with frequent exposure to the creature could be in peril. Several researchers working with the algae have reported bouts of memory loss and disorientation.
To understand the killer algae further, scientists must fully characterize their toxin and determine what stimulates them to attack. They also need to know if the algae are hurting fish populations, and whether pollutants make them more likely to attack.

The word "prompted" underlined in Paragraph 3 means ______.

A. stimulated
B. attracted
C. annoyed

D. shocked