निम्नलिखित में से किसे पारंपरिक रूप से बौद्धिक अक्षमता (intellectual disability) के अंतर्गत वर्गीकृत किया गया है?

Which of the following best describes the principle of 'orderly progression' in child growth and development?

During the early childhood stage, which social and emotional characteristic is most likely to emerge?