All MCQs

Primary-key values are unique and support reliable row identification and relationships.

Asymptotic notation characterises growth rates rather than exact machine-specific time.

Operating systems coordinate processes, memory, storage, devices and user/application interfaces.

Binary uses base two, so each bit has two possible values and positional weights are powers of two.

Limiting permissions reduces the impact of mistakes and compromised accounts.

Testing samples behaviour against expectations; exhaustive proof is usually infeasible.

材料明确说“明天上午九点”，其余时间没有在材料中出现。

汉语基本语序通常是“主语＋时间＋地点/动作”，因此“我今天去学校学习”最自然。

“系统性”可描述性质或状态；其他选项主要是名词或动词。

“重构”表示动作或行为；其余选项主要表示事物、地点、概念或性质。

“合法性”在本题中是名词；其余选项是动作词或性质词，因此不能作为本题要求的名词答案。

材料明确说“明天上午九点”，其余时间没有在材料中出现。