请教下托福TPO22阅读第三篇THE ALLENDE METEORITE

请教下托福TPO22阅读第三篇THE ALLENDE METEORITE
Chondrules and inclusions in Allende are held together by the chondrite matrix,a mixture of fine-grained,mostly silicate minerals that also includes grains of iron metal and iron sulfide.At one time it was thought that these matrix grains might be pristine nebular dust,the sort of stuff from which chondrules and inclusions were made.However,detailed studies of the chondrite matrix suggest that much of it,too,has been formed by condensation or melting in the nebula,although minute amounts of surviving interstellar dust are mixed with the processed materials..
9.According to paragraph 5,which of the following is indicated by studies of the mixture holding the inclusions together?
O Large amounts of this material were formed by condensation or melting in the nebula.
O This material contains more iron and iron sulfide than had previously been thought.
O This material is very similarto the material from which the refractory inclusions are madex05
O The grains in this material are made from the same elements as chondrules ar
e这篇文章看的我有些晕.一下子就没看明白啥意思.求指教啊.题目就有点恍恍惚惚.主要个人语法很烂,我的问题是：
题目没怎么太看明白　：是说：下列哪一项是通过studies of the mixture显示了出来?holding the inclusions together怎么连着翻译好?感觉这题就是段落和选项都看明白了,题目没看懂,
A选项我知道是对的.那比如C选项呢?能不能说下?
再能不能比如具体分析下：However,detailed studies of the chondrite matrix suggest that much of it,too,has been formed by condensation or melting in the nebula……　这个too是什么意思?