On a bar (Gantt) chart for scheduling, individual activities of a project are conventionally represented by which graphical element?

Introduction / Context:
Bar charts are among the simplest and most widely used scheduling tools in construction. Recognising how activities are drawn helps in reading and producing clear schedules for stakeholders.

Given Data / Assumptions:

• We are interpreting the visual convention of a Gantt/Bar chart.
• Each activity has a duration along a time axis.

Concept / Approach:
On a bar chart, time is on the horizontal axis, and activities are listed vertically. The span of an activity over time is shown as a horizontal bar, whose left end indicates start and right end indicates finish.

Step-by-Step Solution:
Recall the layout: activity list on the left, timeline on top.Match the representation: activity duration = horizontal bar segment.Select Horizontal lines.

Verification / Alternative check:
Any standard bar chart image shows activities as horizontal bars aligned against the timeline scale.

Why Other Options Are Wrong:

• Vertical lines: Could indicate milestones or dates, not activity duration bars.
• Dots / Crosses: Used for scatter/milestone markers, not continuous activity spans.

Common Pitfalls:
Confusing milestone markers with duration bars; misreading the axes and believing vertical lines denote work.

Final Answer:
Horizontal lines