Step 1: Think about the conjugate base:
A stronger acid gives a more stable conjugate base. The bases here are $\text{HS}^-$, $\text{HSe}^-$ and $\text{HTe}^-$.
Step 2: Compare sizes:
Negative charge is spread over a larger volume in the bigger ion, so $\text{HTe}^-$ is the most stable and $\text{HS}^-$ is the least stable.
Step 3: Order:
Stability of the base follows $\text{HS}^- < \text{HSe}^- < \text{HTe}^-$, so acidity runs $\text{H}_2\text{S} < \text{H}_2\text{Se} < \text{H}_2\text{Te}$. This is exactly option (A); the other options break this size trend.
Final Answer:
The acidity order is H2S < H2Se < H2Te.
\[ \boxed{\text{(A) }\text{H}_2\text{S}<\text{H}_2\text{Se}<\text{H}_2\text{Te}} \]