In a linguistically diverse and multicultural English language classroom, educators frequently encounter various forms of learner interlanguage errors, developmental divergences, and interference phenomena. Consider the following four advanced propositions regarding the pedagogical management of language difficulties and learner errors: I. Interlingual errors are primarily caused by the negative transfer (interference) of phonological, lexical, or syntactic structures from the learner's native language (L1) into the target language (L2), whereas intralingual errors originate from the incomplete or overgeneralized internal processing of target language rules itself (e.g., applying regular past-tense ed-inflection to irregular verbs like *goed*). II. According to modern error analysis frameworks established by S. Pit Corder, teachers should view student errors strictly as punishable linguistic deviations that must be immediately and harshly eradicated through mechanical rote drills, treating fossilized errors as permanent indicators of cognitive deficiency. III. Fossilization—a phenomenon identified by Larry Selinker in interlanguage theory—describes the permanent cessation of L2 learning progress where incorrect linguistic forms remain entrenched in the learner's speech and writing despite continuous exposure and advanced communicative proficiency. IV. In inclusive classrooms catering to diverse linguistic backgrounds, differentiated instruction and multisensory remedial strategies are vital for diagnosing micro-skill breakdowns, allowing educators to tailor corrective feedback without inducing affective filters or communicative anxiety. Identify the option that correctly evaluates the pedagogical, psycholinguistic, and theoretical validity of propositions I, II, III, and IV according to modern language education methodology and Error analysis principles.