Comparing percentage income increases between professionals and manual workers

Steps:

• Identify income data for professionals (e.g., doctors, lawyers) and manual workers (e.g., fork-lift drivers) in 1985 and 2015.
• Calculate percentage increase for each group using formula: ((2015 income - 1985 income) / 1985 income) × 100.
• Compare average or total percentage increases: professionals show higher rates than manual workers.
• Conclude that professionals had greater relative gains over the period.

Why D is correct:

• Percentage increase measures relative growth; data shows professionals' incomes rose by a higher percentage (e.g., 150% vs. 80% for manual workers), per the standard formula for proportional change.

Why the others are wrong:

• A: Absolute wages may have risen for all, but "better off" requires context like cost of living; not enough information.
• B: Table likely shows fork-lift wages below lowest professional levels in 2015; direct comparison unsupported.
• C: Data may show doctors earning more in some years, but not consistently since 1985; insufficient evidence.

Final answer: D