Which of these is a characteristic of science?

it is based on views and opinions.
it is guided by values like trust and truth.
it find answers to questions which are not testable.
it gives the same result when experiments are repeated.

The correct answer is D. It gives the same result when experiments are repeated.

Explanation:

Science refers to a system or discipline that aims at understanding phenomena that is testable mainly through multiple observations, hypotheses, and testing. Because of this, characteristics of science include that it is based on facts or ideas that have been proved, it is useful for answering testable questions and also the findings are replicable which means if tested multiple times same results would be obtained which proves phenomenons and events are facts and do not depend on opinions or personal views. Considering this, the one that is a characteristic of science is that "It gives the same result when experiments are repeated".

the child will have heterozygous dominant chromosomes as characters of his father are dominant over the characters of his mother.

the child is heterozygous

1. the question asks the most appropriate, which seems to rule out "all of the above." your choice appears to be the correct one.

2. the protocol described is good for identifying correlation, but not cause and effect. for cause/effect, you need to devise a protocol that will assign the treatment (or not) to groups that have essentially the same "demographics" with respect to all the other variables. your choice regarding control group seems appropriate. random assignment of treatment (choice d) may be appropriate also. (i think you can argue that b and d are just different descriptions of the same method.)

3. d will randomize the birds, but may not guarantee there are 10 in each group. e will do both, so seems the better choice.

comment on question 2

based on the problem statement, it seems clear that confident, attentive drivers are more likely to use daytime running lights. so, the protocol might need to be devised in such a way that the lights would be turned on or off without the driver's knowledge. (an attentive driver will figure it out.) assigning a confident, attentive driver to a group required to drive without running lights might mess with his/her confidence and attentiveness. you don't want your experiment to do that. (nor do you want the experiment to subject a driver to greater risk of accident as a consequence of driving without running lights.) experiments involving human safety are always problematic.