  We propose that the flux-rope $\Omega$ loop that emerges to become any
bipolar magnetic region (BMR) is made by a convection cell of the
$\Omega$-loop's size from initially-horizontal magnetic field ingested through
the cell's bottom. This idea is based on (1) observed characteristics of BMRs
of all spans ($\sim$ 1000 km to $\sim$ 200,000 km), (2) a well-known simulation
of the production of a BMR by a supergranule-size convection cell from
horizontal field placed at cell bottom, and (3) a well-known convection-zone
simulation. From the observations and simulations, we (1) infer that the
strength of the field ingested by the biggest convection cells (giant cells) to
make the biggest BMR $\Omega$ loops is $\sim$ 10$^3$ G, (2) plausibly explain
why the span and flux of the biggest observed BMRs are $\sim$ 200,000 km and
$\sim$ 10$^{22}$ Mx, (3) suggest how giant cells might also make "failed-BMR"
$\Omega$ loops that populate the upper convection zone with horizontal field,
from which smaller convection cells make BMR $\Omega$ loops of their size, (4)
suggest why sunspots observed in a sunspot cycle's declining phase tend to
violate the hemispheric helicity rule, and (5) support a previously-proposed
amended Babcock scenario for the sunspot cycle's dynamo process. Because the
proposed convection-based heuristic model for making a sunspot-BMR $\Omega$
loop avoids having $\sim$ 10$^5$ G field in the initial flux rope at the bottom
of the convection zone, it is an appealing alternative to the present
magnetic-buoyancy-based standard scenario and warrants testing by
high-enough-resolution giant-cell magnetoconvection simulations.
