字母数字标识符是标识某物的字母和数字的组合。

An alphanumeric identifier is an assembly of characters and numbers. It can recognize something.

An symbolic-numeric identifier is an assembly of symbols and numbers. It can identifies something.

An alphanumeric identifier is a combination of letters and numbers that identifies something.

正确答案：C

This data module tells you how to operate the unit.

Speed-Attitude Correction system automatically maintains a safe flight attitude by correcting for effects of speed.

Illustrations showing location of attachment points, turning radius shall be included.

A system is a combination of interrelated components arranged to perform a specific function.

Appropriate revision pages and related effectivity page lists will be provided when amending the basic document.

Manufacturers may omit systems not applicable to their product.

Use some auxiliary screws to assemble the unit temporarily.

Only approved persons are permitted to stay in this area.

If the components fall, permanent damage can occur.

The door is made of carbon fiber reinforced plastic.