Answer:
A valid reason for concluding that your classmate and his sister may have been undernourished for several years upon seeing a picture of them from that time period could be:
**Visible Signs of Malnutrition:** If the picture shows visible signs of malnutrition, such as emaciation, prominent bones, distended bellies, sunken eyes, or signs of stunted growth, these physical indicators can strongly suggest that the children were not receiving adequate nutrition for an extended period. These signs of malnutrition may include skeletal features that appear more pronounced due to a lack of proper nourishment.
It's important to approach this situation with sensitivity and empathy, as discussions about past experiences with malnutrition can be personal and potentially sensitive topics for individuals who have experienced them.
Step-by-step explanation: