「品質の問題」により却下された理由

There's little to no commercial value for this one.

Compare with current Stock inventory.  You're competing with 24.3 MILLION results for Sky with Tree.

https://stock.adobe.com/search?k=sky+with+trees  

100％に拡大してチェックしてから提出していますか？

PCの画面で等倍で表示してみると、ノイズが多いのとピントの合っていない画像が含まれています。

こういった写真はまず間違いなく審査に通りません。

また、ハイライトの飛びとシャドウの潰れもチェックの対象なので、LightroomやPhotoshopなどで修正してから提出するようにします。

風景写真だと見逃がしがちですが、看板などにある文字やロゴが入っていても審査に通りません。

修正してから提出する必要があります。

ap_20254029_A7 (24).jpg - very underexposed in the shadows

All of your photos need post processing. 
I see errors like unlevel horizon, underexposed shadows, overexposed highlights, unwanted objects (such as wires on the photo of a tree) and cropping issues.
Example:

Your first: It's a nice picture, but you need to augment sharpness (focus?) and reduce the noise. Reducing noise is possible if done carefully, but correcting the sharpness is difficult. It is not easy to correct a picture that is lacking sharpness out of the camera. 

In addition, to avoid intellectual property refusals, you need to edit out logos and company names like here: : 

Your second is oversaturated, especially in the blues, and has an exposure issue, as shown in the histogram:

Your third: oversaturated and noisy. I did not check the exposure or any other possible defect.

Your fourth: Sensor dust: 

(When you know that you have a sensor dust issue, you can easily correct that. If you have multiple issues, you will need to clean the sensor.) The picture is also missing contrast, and you could enhance the texture/clarity. Be careful, not that you add or amplify the noise too. Be careful, not that you add or amplify the noise too. 

Your last: blown-out whites (clouds in the sky need to have structure, the white sign at the end of the path), on the other side you need to lift the shadows. I'm not sure, but the image could also get a push in sharpness.