The passive voice is formed using 'to be' and the past participle of a verb and typically includes a 'by' phrase. Option B uses 'was' and 'written', the passive form of 'to write', and has a 'by' phrase. Options A, C, and D are in the active voice. * **Core考点:** 被动语态的运用 * **解题思路:** 识别被动语态的构成形式 * **选项分析:** * A: 错误，主动语态。 * B: 正确，被动语态，包含 'was + 过去分词' 结构。 * C: 错误，主动语态。 * D: 错误，主动语态。 * **易错点:** 将主动语态误认为被动语态。