In a multilingual and inclusive classroom setting, educators must distinguish between various manifestations of language difficulties, interlanguage development, and student errors. Consider the following four advanced propositions regarding error analysis and language teaching challenges: I. Intralingual and developmental errors (such as overgeneralization of regular past-tense inflections to irregular verbs, e.g., 'goed' or 'brung') typically occur when a learner applies target language rules too broadly, reflecting active cognitive hypothesis-testing rather than mere first-language interference. II. Interlingual errors are exclusively caused by the complete absence of any grammatical structures in the target language, requiring immediate punitive conditioning and rote memorization to eradicate native language habits permanently. III. Fossilization, a concept identified by Larry Selinker in interlanguage theory, describes a permanent cessation of learning in certain linguistic items, structures, or phonological features, where persistent errors become entrenched despite continuous exposure to the target language and formal instruction. IV. Code-switching in a diverse classroom should invariably be treated as a severe cognitive deficit and a pathological language disorder that impedes academic achievement, rather than a sophisticated communicative resource used by bilingual speakers for pragmatic emphasis and peer bonding. Identify the option that correctly evaluates the pedagogical, linguistic, and theoretical validity of propositions I, II, III, and IV according to second language acquisition theory and Error Analysis principles.