While engaging students who are visually challenged, teachers should use __________ which __________.

Correct Answer: Braille, is a tactile system.

Step-by-Step Explanation:

1. Understanding the Needs of Visually Challenged Students:
Students with visual impairments have limited or no vision. Therefore, educational strategies and teaching-learning materials (TLMs) must rely on alternative senses, such as touch (tactile) or hearing (auditory), to help them process information effectively.

2. Analyzing Braille and its System Type:
- Braille is a tactile writing system used by people who are visually impaired. It consists of raised dots that can be read with the fingers.
- Since Braille relies on the sense of touch, it is categorized as a tactile system.

3. Filling in the Blanks:
Placing "Braille" in the first blank and "is a tactile system" in the second blank completes the sentence accurately:
"While engaging students who are visually challenged, teachers should use Braille which is a tactile system."