Final answer:
In the growth-share matrix, 'question marks' are identified as low-share business units in high-growth markets. These SBUs need heavy investment to grow their market share, and they carry potential for future success.
Step-by-step explanation:
The growth-share matrix, also known as the BCG matrix, defines four types of strategic business units (SBUs) based on their market growth rate and relative market share. Question marks are described as: a. low-share business units in high-growth markets. These are businesses or products that operate in a rapidly growing market but have not yet achieved a dominant position. They require significant investment to increase their market share, but they also hold potential for growth and eventually becoming 'stars' if they succeed in increasing their market share.