从古至今，对于绝大多数的富翁来说，他们对于财富的处理，一般是全部留给子孙，这对他们来说，是______的，也是他们一贯的做法。但是在美国的富翁中，近年来却有一种新的风尚在流行，那就是不要留太多的财产给子孙后代。以免他们______，都成了扶不起的刘阿斗。 填入横线部分最恰当的一项是( )。

A．理所当然 乐不可支

B．天经地义 乐不可支

C．天经地义 乐不思蜀

D．理所当然 乐不思蜀

An embedded operating system is the (71) program that manages all the other programs in an embedded device after initial load of programs by a(an) (72). It normally guarantees a certain capability within a specified (73) size and (74) constraint as well as with application programs. It also normally has small foot print including initial boot loader, OS kernel, required device drivers, (75) for the user data and so forth. It has very-likely structure of a normal operating system however mainly differentiated by some factors such as type of pre-installed device, functional limits, taking designed job only.

A．data

B．storage

C．bus

D．CPU