2. when thomson held a positively charged plate near the cathode ray, the beam bent toward the plate. what conclusion can be drawn from this observation? (2 points)
the beam was made of light.
the beam was positively charged.
the beam was negatively charged.
the beam was made of neutrons.

option B is correct :  The beam was positively charged.

Explanation:

In 19th century J.J Thomson conducted an experiment on cathode ray tube. These cathode ray tubes were sealed glass tubes inside which the pressure of the gas reduced by evacuating air. Then he applied a high voltage across two electrodes at end of the tube, that voltage caused a beam of particles to flow from the cathode to the anode.

Beam of the particles were originated at the cathode and detected on anode by a phosphorous beyond the anode. As at that time phosphorous sparks and emit light.

To test properties of particles he places two opposite charged electric plates around the cathode rays that is one negative and one positive plate.

Thomson observed that these rays deflected to positive electric plate so it indicated that these rays are composed of negatively charged particles as it was attracted by the positive charged electric plate. These particles later named as electrons.

So,

option B is correct :  The beam was positively charged.

i believe you are right for all except the 3rd ( look at sqdancefan his answer is much better)