Explanation:

- Analyzing the given equation: $26÷24+6\times 27-105=29$.

- Option 1: Swap $\times$ and $÷$:

- New equation: $26\times 24÷6+27-105$.

- Simplifies to $104+27-105=26$, incorrect.

- Option 2: Swap $+$ and $÷$:

- New equation: $26+24÷6\times 27-105$.

- Simplifies to $26+4\times 27-105=29$, correct.

- Option 3: Swap $+$ and $\times$:

- New equation: $26÷24\times 6+27-105$.

- Simplifies to $6.5+27-105=-71.5$, incorrect.

- Option 4: Swap $\times$ and $-$:

- New equation: $26÷24+6-27\times 105$.

- Results in a large negative number, incorrect.

The correct answer is Option 2: Swap $+$ and $÷$.