Final answer:
Systematic instruction in teaching decoding and blending skills for reading is highly supported by research. This structured, step-by-step method is essential for effective reading education.
Step-by-step explanation:
The correct answer to fill in the blank for the sentence 'Explicit, _____________, cumulative instruction that teaches students to decode graphemes and blend the corresponding phonemes and/or syllables received stronger support in high-level research than other types of instruction.' is systematic. This means that when teaching students the foundational skills of reading, such as decoding and blending, a structured, step-by-step approach is strongly supported by research. This approach, known as systematic instruction, has been shown to be effective for learning to read because it builds upon skills in a sequential and logical order, often with plenty of repetition to ensure mastery before moving on to more complex tasks. This contrasts with implicit, passive, and repetitive methods that do not necessarily offer the same research-backed benefits for reading instruction.